so have you taken a good hard look at the 4th and 12 play? because it sums it up quite nicely.
mosley, assigned to the deep seam/hash, lines up for an A-gap blitz, this is crucial and ill explain later...
weddle, showing blitz pre-snap, left running at the snap to get to his deep zone(cant remember if he was covering a third, half, or quarter, this is irrelevant anyway)
canady blew this one, because on 4th and 12 he lined up about 16 yards deep and still appeared to be playing man coverage somehow, horrible play by him but if hes 4-6 yards off the line then he can disrupt boyd enough to let mosley and weddle get to their zones.
but back to the first. mosley was seen leaping very high to try to bat down the pass, the pass fell between mosley, weddle, and canady, mosley is one to commonly get very high up to snag a ball, the boys got some bunnies, but he was about 4 yards out of position, if he was 4 yards closer to the hash from where he started, hes in position and that ball is picked. if he was lined up off the ball, or showing an edge rush, he is without question in position to defend that pass. hes assigned to a deep outside-ish zone, but is lined up between 2 DTs in the A gap, he is fucked from the start if the bengals do anything but run a comeback in the seam, but its 4th and 12 so you can obviously expect they wont be doing no dumb shit like that.
dalton probably knew right away, weddle isnt blitzing, so take a quick peek before the snap and then disregard that, and then one look at mosley(who is directly in front of his face) running away from the LoS and he knows hes fucked and wont be anywhere near the play if he targets boyd. he knew the second the ball was snapped, that he had one person to really worry about, and that was canady, who was lined up deeper than the sticks on 4th and 12 so he could run unimpeded to the soft spot and get there before the primary defenders. dalton was comfy as fuck and so was boyd and they knew they had at worst an easy pitch and catch for a first down the moment the ball was snapped.